What Makes a Roller Coaster 4D?
A fourth-dimension roller coaster rotates riders independently of the track orientation, generally about a horizontal axis perpendicular to the track. The carts do not need to be fixed to an angle. These coasters are called "fourth dimension" because the spinning seats add a direction independent of the track, like a fourth dimension.
History of 4D Roller Coasters
X at Six Flags Magic Mountain was the first fourth-dimension coaster when it opened in 2002. Arrow designed X but went bankrupt completing it. S&S Power purchased Arrow and built another fourth-dimension coaster in 2006, Eejanaika at Fuji-Q Highland in Japan.
The Experience of Riding a 4D Coaster
On these coasters, the seats cantilever on each side of the vehicle, allowing 360-degree rotation. Wheels on ratchet gears under the seats connect to gears in the vehicles to spin the seats as special rails adjust position. The spinning gives an intense ride, making fourth-dimension coasters the most insane and intimidating.